Thanks for your question on Healthcare Magic. 
I can understand your concern. 
No, it is not true that your life expectancy is 5-7 years only. 
If you reduce weight and 
cholesterol level, your 
angina will definitely improve and so as your life expectancy. 
Follow these to achieve low cholesterol level. 
1.  Do regular 
aerobic exercise like running, cycling, swimming etc. 
2. Avoid oily and fatty food. 
3. Avoid junk food. Avoid fast food. 
4. Take high fiber diet like green leafy vegetables, fruits etc. 
5. Use sunflower oil for cooking. 
6. Start lipid lowering drug like rozuvastatin or 
atorvastatin. 
Your cholesterol level willing definitely reduce with all these. 
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.